Bus bar housing with externally attached bus bar supporting insulators



F. E. A. COGNET ETAL BUS BAR HOUSING WITH EXTERNALLY ATTACHED BUS 3,221,097 BAR Nov. 30, 1965 SUPPORTING INSULATORS Filed April 28, 1961 FIRM/IV E057/CHE MAI/D ('OG'YIT LUd EA/ LEG/V Mai/IR 5r M7 I 3,221,097 Patented Nov. 30, 1965 United States PatentOfiFice 3,221,097 BUS BAR HOUSING WITH EXTERNALLY AT- BUS BAR SUPPORTING INSULA- Firmin Eustache Armand Cognet, Paris, and Lucien Lon Mohier, Maisons-Lafiitte, France, assignors to Societe anonyme dite: Societe General dExploitations Industrielles, a corporation of France Filed Apr. 28, 1961, Ser. No. 106,329 Claims priority, application France, May 6, 1960, 826,687, Patent 1,264,074 9 Claims. (Cl. 174-99) This invention relates to improvements in conductive bars surrounded by continuous sheaths.

Various arrangements are known in which electric cur rent conductive bars are placed on insulators inside closed metallic sheaths.

Some of these arrangements include so-called continuous sheaths, i.e. the sheaths not only constitute an electrical continuity over practically their complete length, but they also form a mechanically r-igid assembly which could be actually designated by the more descriptive expression of continuous piping.

The difiiculties encountered in using continuous sheaths of this type result from the fact that the sheaths, as well as the bars they surround, have to be freely expandable and this problem is made difii'cult to solve because the bar and sheath have to be insulated relative to each other and also relative to the ground, so that the known arrangements are generally complex and that their mounting is very delicate.

The present invention has for its object a new arrangement for the assembly comprising a conductive bar surrounded by a continuous sheath, whereby the bar and sheath respectively are capable of expanding freely from fixed points of construction, this arrangement'resulting furthermore in easy mounting of the assembly.

The arrangement in accordance with the invention is characterised by the fact that the insulators carrying the bar are positioned in openings formed in the sheath and are held'therein by way of a flange which is greater in diameter than the sheath opening and is exterior to the sheath, whilst the remaining part of the insulator is so dimensioned as to be able to pass through the sheath opening.

Further characteristics of the invention will appear from the ensuing description of a non-limiting example of embodiment, with reference to the accompanying drawings wherein:

FIG. 1 is a diagrammatic illustration of the problem solved by the present invention.

FIGS. 2, 3 and 4 show the bar insulators in various dispositions.

Shown on FIG. 1 is a sheath portion 1 surrounding a bar piece 2; the bar is supported by sets of insulators 3 and 4 whilst the sheath is held by supporting assemblies 5 and 6. Also shown on the drawing is a fixed point F of the sheath to be later described and a fixed point F of the bar which is obtained by blocking the insulator set 3 by way of stop members T secured to the bar. These fixed points F and F may be adjacent or remote from each other. The insulator set 4 and the supporting assembly 6 enable the bar and sheath to expand freely as will be presently explained.

FIG. 2 is a cross-section in a direction normal to the insulators 4, in which the bar has a substantially square cross-sectional area and the sheath a circular cross-sectional area, but it will be understood that this is by way of example only and that the bar and sheath could have been given a different contour. Also illustrated by way of example are four insulators a, b, c and d supporting the bar, but a different number of these insulators could be used.

Each insulator has a base A fixed on a flange A integral with the sheath. An insulator member B of conventional ceramic material has one of its ends fixed in the base A and carries at its other end a device C for supporting the bar. This device comprises a shoe C sliding in a drum C with the interposition of a compression spring R. The device C is received in the insulator member B through the agency of a ball-joint C and is retained in said member B by a simple ring 0., of flexible rubber or any other elastic material.

The shoe C has a curved face E in contact with the bar, as shown on FIG. 3 which is a longitudinal view thereof. Owing to this curved contour E and to the provision of the device C in accordance with FIG. 2, the bar is able to be displaced relative to the sheath, the device C then assuming an inclined position as shown in FIG. 4, whilst the spring R permanently maintains the bar supporting action of the shoe C FIG. 2 illustrates moreover the possibility of inserting, or removing, an insulator assembly through the sheath wall, and such operation could even be effected in the live condition of the installation.

The sheath itself is carried by supports 5 and 6 on which it is slidable to allow for its free expansion and to this end the sheath includes suitably dimensioned shoes normal to the supports. In order to obtain the longitudinal fixed point F it is sufficient to immobilize a normally free assembly such as 5 by suitably disposing stops T integral with the sheath.

The various characteristics of the invention, as described in the foregoing, permit of an easy mounting and make it possible in particular to weld easily the various sections of sheath and bar on the work place.

The shape of the various components, their number and .the nature of the constituent materials may be modified without exceeding the scope of the present invention.

What we claim is:

1. An arrangement for fixing an electric bar in a metallic sheath in an insulating manner, in which the bar can be displaced longitudinally relative to the sheath under the effect of thermal expansion, comprising a metallic sheath provided with openings of predetermined size, an electric bar within said sheath, and means including a plurality of insulators provided with flanges supporting said bar within said sheath to enable longitudinal displacement of said bar relative to said sheath, the insulators carrying the bar being positioned in the said openings formed in the sheath and being retained therein by a respective flange larger in diameter than the sheath opening and placed on the outer surface of the sheath, whilst the remaining portion of the insulator is so dimensioned as to be able to pass through the sheath opening.

2. Arrangement according to claim 1, wherein the inner end of the insulator which carries the bar, comprises a shoe pivotally connected to a ball-joint and spring means for applying said shoe against said bar.

3. Arrangement according to claim 2, wherein the shoe is carried by a rod sliding in a drum with the interposition of said spring means.

4. Arrangement according to claim 2, wherein the shoe is held in position by a ring of flexible elastic material.

5. Arrangement according to claim 2, wherein the shoe contacts the bar over a curved surface which retains contact with the bar under the various inclinations of the shoe.

6. Arrangement according to claim 1, wherein at least one insulator is blocked longitudinally on the bar by way of stop means secured on the bar and spaced from said one insulator.

7. An arrangement for fixing an electric bar within a sheath in an insulating manner, in which the barcan be displaced longitudinally relative to the sheath under the effect of thermal expansion, comprising sheath means provided with apertures of predetermined size, electrically conductive bar means within said sheath means, and insulating means supporting said bar means in an insulating manner with respect to said sheath means including a plurality of insulating members, each insulating member having a first portion of cross section smaller than said predetermined size to enable introduction thereof through a respective aperture and a second portion of cross section larger than said predetermined size and serving as external abutment so as to enable complete assembly and disassembly of a respective insulating member from the outside of said sheath means, each second portion of a respective insulator member being provided with inwardly facing abutment surfaces engaging substantially complementary outwardly facing surfaces provided on said sheath means, and resilient means operatively associated with a respective insulating member and interposed between a respective insulating member and the bar means to effectively maintain the insulating support of said bar means.

8. An arrangement for fixing an electric bar within a sheath in an insulating manner, in which the bar can be displaced longitudinally relative to the sheath under the effect of thermal expansion, comprising sheath means provided with apertures of predetermined size, electrically conductive bar means within said sheath means, and insulating means supporting said bar means in an insulating manner with respect to said sheath means including a plurality of insulating members, each insulating member having a first portion of cross section smaller than said predetermined size to enable introduction thereof through a respective aperture and a second portion of cross section larger than said predetermined size and serving as external abutment so as to enable complete assembly and disassembly of a respective insulating member from the outside of said sheath means, each second portion of a respective insulating member being provided with inwardly facing abutment surfaces engaging substantially complementary outwardly facing surfaces provided on said sheath means, and resilient means operatively associated with a respective insulating member for effectively maintaining the insulating support of said bar means including spring-loaded engaging members intermediate a respective first portion and said bar means.

9. An arrangement for fixing an electric bar within a metallic continuous sheath in an insulating manner, in which the bar can be displaced longitudinally relative to the sheath under the effect of thermal expansion, comprising continuous metallic sheath means provided with apertures of predetermined size, electrically conductive bar means within said sheath means, and insulating means supporting said bar means in an insulating manner with respect to said sheath means including a plurality of insulating members, each insulating member having a first portion of cross section smaller than said predetermined size to enable introduction thereof through a respective aperture and a second portion of cross section larger than said predetermined size and serving as external abutment so as to enable complete assembly and disassembly of a respective insulating member from the outside of said sheath means, each second portion of a respective insulating member being provided with inwardly facing abutment surfaces engaging substantially complementary outwardly facing surfaces provided on said sheath means, and resilient means operatively associated with a respective insulating member and interposed between a respective insulating member and the bar means to effectively maintain the insulating support of said bar means.

References Cited by the Examiner UNITED STATES PATENTS 2,469,445 5/1949 Scott 17499 2,997,525 8/1961 Powell 174-88 X FOREIGN PATENTS 1,200,923 7/1959 France.

JOHN F. BURNS, Primary Examiner.

G. MILLER, JOHN W. WILDMAN, LAR- AMIE E. ASKIN, Examiners. 

1. AN ARRANGEMENT FOR FIXING AN ELECTRIC BAR IN A METALLIC SHEATH IN AN INSULATING MANNER, IN WHICH THE BAR CAN BE DISPLACED LONGITUDINALLY RELATIVE TO THE SHEATH UNDER THE EFFECT OF THERMAL EXPANSION, COMPRISING A METALLIC SHEATH PROVIDED WITH OPENINGS OF PREDETERMINED SIZE, AN ELECTRIC BAR WITHIN SAID SHEATH, AND MEANS INCLUDING A PLURALITY OF INSULATORS PROVIDED WITH FLANGES SUPPORTING SAID BAR WITHIN SAID SHEATH TO ENABLE LONGITUDINAL DISPLACEMENT OF SAID BAR RELATIVE TO SAID SHEATH, THE INSULATORS CARRYING THE BAR BEING POSITIONED IN THE SAIE OPENINGS FORMED IN THE SHEATH AND BEING RETAINED THEREIN BY A RESPECTIVE FLANGE LARGER IN DIAMETER THAN THE SHEATH OPENING AND PLACED ON THE OUTER SURFACE OF THE SHEATH, WHILST THE REMAINING PORTION OF THE INSULATOR IS SO DIMENSIONED AS TO BE ABLE TO PASS THROUGH THE SHEATH OPENING. 